Auxiliary retention for a c-washer

ABSTRACT

A C-washer normally retained behind a shoulder on a shaft by an end recess on a member carried by the shaft, the C-washer having means adapted to narrow the gap adjacent the opening of the Cwasher after assembly to the shaft, in order to close the gap of the washer to a distance less than the shaft diameter and prevent disengagement of the washer on axial displacement on the member carried by the shaft.

United States Patent 1191 Redding 1 Jan. 9, 1973 1541 AUXILIARYRETENTION FOR A c- 2,658,699 11/1953 Rovas ..85/51 WASHER 2,554,9575/1951 Riblet ..s5/51 1 5] I 1T rE f r fi ifi h- FOREIGN PATENTS ORAPPLICATIONS 1 1,247,760 8/1967 Germany ..85/8.6 [22] Filed: June 25,1971 [21] Appl. No; 156,675 Primary Examiner-Andrew V. KundratAtt0rney-Glenn B. Morse [52] US. Cl ..287/52.07, 287/5208 51 Int. Cl..F16d 1/08 [57] ABSTRACT I [58 Field ofSearclI....85/51, 8.6; 287/D1G.7, 52.08, A C-washer normally retained behind a shoulder on a 287/52.07,53 shaft by an end recess on a member carried by the shaft, the C-washerhaving means adapted to narrow [56] References Cited the gap adjacentthe opening of the C-washer after assembly to the shaft, in order toclose the gap of the UNITED STATES PATENTS washer to a distance lessthan the shaft diameter and 1,747,741 2/1930 Sprung ..85/8.6 preventdisengagement of the washer on axial dis- 2,261,415 11/1941 Schnell..85/51 placement on the member carried by the shaft. 2,341,191 2/1944Orendorff..... ..287/52.08 X 2,210,811 8/1940 Kelpsch ..287/53 1 Claim,6 Drawing Figures PATENTED JAN 9 1973 3. 709,530

INVENTOI? Wilford A. Reddinq Fig. 5 Fly. 6 BY j W A 77' ORA/E YAUXILIARY RETENTION FOR A C-WASI'IER BACKGROUND OF THE INVENTION It iscommon practice to prevent a member carried by a shaft from slipping outof engagement with the shaft through the use of a C-washer engaging agroove in the shaft, and projecting radially beyond the shaft peripheryto function as an abutment. The C-washer is conventionally retained inplace in a variety of ways. One of these is to grip the ends of thewasher with sufficient force to wrap it around the shaft to a point thatthe gap is closed to a dimension less than the shaft diameter. Thisversion of the C-washer is occasionally referred to as a clinch ring. Inthe larger sizes of these devices, this type of closure becomesextremely difficult, particularly in applications where access islimited. Other systems for maintaining the engagement of the C-washerwith the shaft include a lateral press fit, and a related arrangementinvolving a sufficient resilience of the C-washer to permit it to beforced open to a slight degree in the process of engagement with theshaft, with an internal configuration permitting the resilience to closethe device slightly around the shaft after arriving at fully assembledposition. One very frequently used retention arrangement involves theformation of a recess on an axial end of a member carried by the shaft,with the recess being of a diameter sufficient to receive the exteriorof a C-washer loosely slipped into a groove on the shaft. As long as theC- washer is retained within the recess, sufficient lateral movement todisengage it from the shaft is impossible. A problem arises, however, ifaccumulations of tolerance or wear permit sufficient axial displacementof the member with respect to the shaft to permit the C- washer to moveout of the confinement of the recess. It is this type of situation thatwas primarily responsible for the development of the present invention.This form of assembly is commonly used in connection with axle shafts onautomobiles and trucks. The rear axle of these vehicles is rotatablysupported in the axle housing, and extends inward to a point where itsupports a bevel gear associated with the differential assembly. Thisbevel gear becomes the member provided with a recess on its inner face,and a heavy C-washer engages a groove in the shaft at a point where thewasher will normally be retained against lateral displacement by beingreceived within this recess. The gear is rotatably restrained againstrotation with respect to the shaft by a standard spline interengagement.In the event of unusual accumulations of tolerance, or of sufficientwear against the thrust bearing surfaces of the axle housing, cases havebeen encountered quite frequently in which the gear will move withrespect to the shaft to a position in which the C-washer is no longerconfined against slipping off the shaft. This is an extremely dangeroussituation, as this condition will permit the entire wheel assembly,including much of the brake system to move freely out of the car. Thisusually happens with no warning at all, and can take place at sufficientspeeds to produce extreme danger to the occupants of the vehicle, and toother vehicles proceeding in that neighborhood. The objective of thepresent invention is to provide an auxiliary retention means that willmake this sort of occurrence impossible, and without requiringadditional installation access or costly modification of conventionaldifferential assembly structure.

SUMMARY OF THE INVENTION A C-washer is provided with means adjacent oneof its ends which may be used to narrow the gap after assembly to theshaft to a point where the distance across the gap is less than thediameter of the portion of the shaft engaged by the gap. The preferredform of the invention utilizes a set screw traversing the material ofthe C-washer at a point adjacent the end, and in a position where it canbe rotated by application of a tool from the side (with respect to theshaft) to a point where it can move inward so that its inner end isdisposed at a distance from the opposite side of the washer less thanthe shaft diameter at the base of the groove which receives the washer.This arrangement is preferable primarily because of its smallrequirement of access, as the set screw can be of the type manipulatedby either a small screw driver or a so-called Allen wrench, which isnothing but a small piece of steel of hexagonal cross-section. Amodified form of the invention, which can be used in applications whereit is possible to apply a punch or hammer to the end of the C- washerinvolves the use of a notch which produces a point of localized bendingunder relatively small forces, with the result that a relatively lighttap applied through a tool to the extreme end of the C-washer willresult in bending the projecting portion down into a position where thegap is sufficiently closed to retain the washer in position. In contrastto the clinch ring arrangement mentioned in the discussion of thebackground of the invention, this system does not require the mechanicto apply forces across the gap in order to close it, or to bend theentire ring sufficiently to wrap it around the shaft.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation of a conventionalvehicle rear axle, engaged by the bevel gear, with the assembledrelationship being maintained by a C-washer received in a recess in theend of the gear.

FIG. 2 is a side elevation of the assembly shown in FIG. 1, showing theuse of a C-washer embodying the present invention.

FIG. 3 is a section on the plane 33 of FIG. 2.

FIG. 4 is a section on an enlarged scale on a plane perpendicular to theaxis of the shaft, and illustrating the arrangement for retaining thewasher in position.

FIG. 5 is a plan view of a modified form of the invention, in theinitial condition prior to assembly with a shaft.

FIG. 6 is a view similar to FIG. 5, but showing the washer deformed intoretaining position after assembly with the shaft.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1, 2, and 3,the shaft 10 has a splined end 11 receiving a gear generally indicatedat 12, and having a hub 13 provided with an internal spline interengagedwith the shaft spline 11. The gear 12 is retained in assembledrelationship with the shaft by the presence of the C-washer 14 receivedin the annular groove 15 in the end of the shaft 10. The gear 12 has arecess 16 in the end adjacent the washer 14, with the diameter of therecess being slightly in excess of the exterior diameter of the washer.The axial depth of the recess 16 is preferably at least equal to thethickness of the Cewasher 14.

To prevent the C-washer 14 from slipping laterally out of engagementwith the shaft on displacement of the gear 12 to the left, as shown inFIGS. 1 and 3, the set screw 17 is engaged with an appropriatelythreaded hole 18 adjacent the end 19 of the washer 14, and this setscrew can be rotated into the position shown in FIG. 4 to retain thewasher against displacement to the left. The original gap 20 of theC-washer is thus reduced to the smaller gap 21, which is less than thediameter of the shaft at the base of the groove 15. The axis of the setscrew 17 will normally be disposed in a plane perpendicular to the axisof the shaft 10, and it is preferrable that the axis of the set screw 17be slightly askew to a radius of the shaft axis. This arrangementgenerates a small degree of binding action as the end of the set screwengages the surface of the shaft and in forced sideways, tending toinhibit a loosening of the set screw.

In the modification shown in FIGS. 5 and 6, the C- washer 22 is providedwith a notch 23 providing an area 24 of locally reduced resistence tobending. The initial gap 25 of this C-washer is thus closeable to thegap shown at 26 in FIG. 6, which is less than the diameter of theembraced shaft 27 at the base of the groove.

Both of these modifications of the invention are easily reset to permitdis-assembly of the shaft and gear, the FIG. 4 arrangement by backingoff the set screw 17, and the FIG. 6 arrangement by the insertion of ascrew driver or punch under the deformed end 28 to pry it back to theFIG. 5 position. Neither of these modifications of the invention requirethe application of forces to more than one end of the C-washer.

I claim:

1. In combination with a shaft having means forming a shouldertransverse to the axis of said shaft, and a member carried by saidshaft, said member having a recess in an axial end thereof, a C-washerhaving a gap adapted to slip over said shaft laterally and engage saidshoulder axially, the exterior of said washer being receivable in saidrecess to maintain the lateral engagement of said washer with saidshaft, wherein the improvement comprises: adjustable means on said C-washer adjacent an end of said washer defining the opening of said gap,and adapted to narrow said gap exclusively at said means to a distanceless than the diameter of said shaft received in said gap, saidadjustable means including a set screw traversing said washer on an axisdisposed in a plane transverse to the axis of said shaft.

1. In combination with a shaft having means forming a shouldertransverse to the axis of said shaft, and a member carried by saidshaft, said member having a recess in an axial end thereof, a C-washerhaving a gap adapted to slip over said shaft laterally and engage saidshoulder axially, the exterior of said washer being receivable in saidrecess to maintain the lateral engagement of said washer with saidshaft, wherein the improvement comprises: adjustable means on saidC-washer adjacent an end of said washer defining the opening of saidgap, and adapted to narrow said gap exclusively at said means to adistance less than the diameter of said shaft received in said gap, saidadjustable means including a set screw traversing said washer on an axisdisposed in a plane transverse to the axis of said shaft.